The speedometer in my 67 started a funny behavior and then stopped working. I have a Tremec TKO in this car and just wanted your opinion and/or experience. Should I get it repaired, or convert to electronic?

 

If you go electronic (which I did), leave your speedo intact and store or sell it. Buy a face ($25), a needle ($27), and the conversion ($300). The electronic has an odometer and trip feature, but you won't have anything in your original trip window. My car is undergoing some major mods so I haven't driven it yet but the speedo self-tests correctly with ignition on. It's an easy hook up, I'm not a fan of cables and use an electronic tach also.

 

I went electronic tach and speedo, AUTOMETER, liked the similar color match. Did a 120 speedo to use more of the sweep.

 

I faced a similar decision a couple years ago. I did a lot of research and ultimately bought an electronic speedo. When connected, I could never get it to calibrate. The place that sold it to me has stopped talking to me. I don't know if the electronic unit is finicky, or if I did something stupid, or if it was "bad" to begin with, etc. I offered to buy a whole 'nother electronic unit and they don't answer my emails. So, I'm at the stage where I've got my mechanical speedo working correctly again showing the correct speed (changed the gear) but the odometer and tripometer still don't work. I've wasted $300 on the electronic speedo conversion which I bought from a small business shop and I think they buy this piece from somebody else and they don't have any expertise on it they just resell it to make a dime. So, they can't do anything with replacement or trouble shooting. I'm pretty much just screwed on that at this point. I can buy another one from another place and hold my breath and hope it's good. Or, just say to heck with it and keep using the mechanical as it shows the right speed at least.

Point of all this, the aftermarket stuff sometimes doesn't work and then what do you do? Don't do what I did. Don't buy the best deal you can get from a middleman.

If you buy something electronic, be sure to buy it direct from the manufacturer with a full warranty.

 

I have a 67 as well, with a TKO 500. My speedometer stopped working. The speedo cable had seized, and the plastic speedo gear was worn down to nothing. Glad it is plastic. New parts, problem fixed. No need for a new speedometer.

 

I bought the electronic speedo conversion from Zip Corvette. I could not get it to calibrate it as well. It powered up and set up to calibrate as well but failed to calibrate. I really do not look forward to pulling the dash out again.

 

The cable casing can be the problem. The grease/lube over the years get solidified and can cause the cable to slowly bind to the point of snapping. If or when you pull the cable, get a suitable wire with a very small piece of cloth pinched in the end and soaked in carb/brake cleaner. Next spray some carb or brake cleaner down the casing. Insert the wire, work it in and out, change the cloth, respray. This should clear the casing. Replace the cable, put some specific lube for speedometer cables. This same effort fixed my problem several years ago. Dennis